An Islam Primer

Everything you always wanted to know, from Islam's 'golden age' to the meaning of 'jihad.'

Islam is the second-largest religion in the world. Religion estimated followers:

Christianity 1.9 billion

Islam 1.3 billion

Hinduism 900 million

There are two main branches of Islam:

Sunni 83%

Shi'ite 16%

Other 1%

Largest Muslim populations (in millions) by CountryNumber of Muslims:

Indonesia 170.3

Pakistan 136

Bangladesh 106

India 103

Turkey 62.4

Iran 60.7

Egypt 53.7

Nigeria 47.7

China 37.1

FIVE PILLARS OF FAITH: Followers of Islam share a core of basic beliefs on which they base their daily lives.

Profession of faith ("shahadah," in Arabic) - "There is no deity but Allah, and Mohammed is his messenger." Followers repeat this phrase several times a day to remind themselves of God's central position in their lives.

Ritual worship ("salah") - Muslims are required to pray formally five time a day-at dawn, midday, afternoon, evening and night.

Almsgiving ("zakah") - Muslims pay a specified amount of money, typically 2.5 percent of their accumulated wealth each year, to assist the poor and sick.

Fasting ("sawn") - During the monthlong Ramadan, Muslims are to refrain from eating, drinking, smoking and sexual activities from dawn to sunset.

Pilgrimage to Mecca ("hajj") - Islam requires every believer to make at least one visit to Mecca in their lifetime if means are available. More on the Hajj...